Quality of Service Guide QoS and QoS Policies
Edition: 01 3HE 11014 AAAC TQZZA 51
• The shaper group of a LAG SAP can be changed to a non-default shaper group
only if the new shaper group exists in the shaper policies used by all adapter
cards of all LAG port members.
• A shaper group cannot be deleted if it is assigned to unshaped SAPs
(unshaped-sap-shaper-group command) or if it is used by at least one LAG
SAP or non-LAG SAP.
• The shaper policy assigned to an adapter card cannot be changed unless all of
the SAPs on that adapter card are assigned to the default shaper group.
3.1.10 QoS for Hybrid Ports on Gen-2 Hardware
This section provides information on QoS for hybrid ports on Gen-2 adapter cards
and platforms. For information on Gen-3 adapter cards and platforms, see QoS for
Gen-3 Adapter Cards and Platforms.
In the ingress direction of a hybrid port, traffic management behavior is the same as
it is for access and network ports. See Access Ingress and Network Ingress.
In the egress direction of a hybrid port, access and network aggregate shapers are
used to arbitrate between the bulk (aggregate) of access and network traffic flows.
As shown in Figure 8, on the access side (above the solid line), both the access
egress SAP aggregates (#1) and the unshaped SAP shaper (#2) feed into the access
egress aggregate shaper (#3). On the network side (below the solid line), both the
per-VLAN shapers (#4) and the unshaped interface shaper (#5) feed into the network
egress aggregate shaper (#6). Then, the access and the network aggregate shapers
are arbitrated in a dual-rate manner, in accordance with their respective configured
committed and peak rates (#7). As a last step, the egress-rate for the port (when
configured) applies backpressure to both the access and the network aggregate
shapers, which apply backpressure all the way to the FC queues belonging to both
access and network traffic.
As part of the hybrid port traffic management solution, access and network
second-tier shapers are bound to access and network aggregate shapers,
respectively. The hybrid port egress datapath can be visualized as access and
network datapaths that coexist separately up until the access and network aggregate
shapers at Tier 3 (#3 and #6).
Note: Due to space limitations in Figure 8, the second-tier, per-SAP and per-VLAN
aggregate shapers are represented as a single loop containing the label “per SAP” or “per
VLAN”, even though they are dual-rate shapers similar to the third-tier network aggregate
shaper. Tiers are labeled at the top of the figure.
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